I could be wrong, but having spent a few years building props and sets, I'm 99% certain the Pinewood art departments recycled all or most of the previous Falcon set pieces for use in Solo. In some cases, it's cheaper to simply rebuild a set from scratch rather than pay to store it, but since they're shooting these movies practically back to back at Pinewood, it would be wasteful not to carry over some or all of the Falcon set between films. Almost always those big sets are designed to be disassembled in sections for storage, transportation, or to reassemble in various configurations on the stage depending on the nature of the scenes being shot. For example, the full 360 Falcon set built for TESB in 1978 was put into storage for use in ROTJ, but when they shot the sandstorm scene a few years later they didn't reassemble the entire ship, just the cockpit side. These sets are basically plywood skins over metal armatures that support all the weight. For Solo, they'd have to remove all the junky greeblies of the older, used-look Falcon and redress it to look new, but I would be very surprised if they didn't reuse the metal armatures and many of the signature Falcon details, like the boarding ramp, landing gear, and Cockpit cone. I'm happy to be proven wrong, but making Lando's version 5-gear instead of 3 is likely an example of form following function.